DNA polymerase or taq enzyme used in PCR is isolated from

Options

A. Thermus aquaticus
B. E. coli
C. Salmonella typhimurium
D. None of the above

Answer

**Step-by-Step Solution:**

1. **Understanding PCR**:
- PCR stands for Polymerase Chain Reaction, which is a technique used to amplify DNA sequences.

2. **Identifying the Enzyme**:
- The enzyme used in PCR is known as DNA polymerase, specifically the Taq polymerase.

3. **Source of Taq Polymerase**:
- Taq polymerase is derived from a bacterium called *Thermus aquaticus*.

4. **Environment of *Thermus aquaticus***:
- This bacterium is found in hot springs, where it thrives in high-temperature environments.

5. **Importance of Taq Polymerase**:
- Taq polymerase is particularly suitable for PCR because it remains active at a wide range of temperatures, which is essential for the denaturation and annealing steps of the PCR process.

6. **Historical Context**:
- The bacterium *Thermus aquaticus* was first discovered in 1969, and its enzyme was later utilized for PCR due to its heat stability.

7. **Conclusion**:
- Therefore, the DNA polymerase or Taq enzyme used in PCR is isolated from *Thermus aquaticus*.

**Final Answer**: The DNA polymerase or Taq enzyme used in PCR is isolated from *Thermus aquaticus*.

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